This invention relates generally to the treatment of gases and is particularly useful in the extraction of contaminants from compressed gas, such as oil and water vapors. More specifically, the invention relates to method and apparatus employing a filter for removing oil vapor from process gas and a vortex tube for producing a low temperature gas required for the condensation of water vapor in the process gas with a heat exchange relationship.
In the past, there have been dehumidification systems devised wherein a cooling process is used to condense the water vapor contained in a stream of compressed air or other gas. Most of these prior systems are characterized by a structural complexity that results in an unduly high production cost. Furthermore, the various cooling units utilized by existing systems typically require a substantial amount of external power in order to properly cool the gas, which leads to excessive operating and utility costs.
The present invention overcomes these and other disadvantages of the prior art systems by providing a structurally simple apparatus for drying gases and extracting oil vapor therefrom. Oil vapor in the process gas is first trapped in a filter and the gas is then split into primary and secondary streams. A vortex tube operates without an external power source to lower the temperature of a portion of the secondary stream which is then passed through a heat exchanger to cool the primary stream and condense water vapor therefrom.
An object of this invention is to provide a method and apparatus for removing oil and water vapors from compressed gas.
Another object of the invention is to provide a cooling unit having no moving parts for condensing the water vapor contained in a process gas.
Yet another object of the invention is to provide gas drying apparatus wherein the energy of a portion of the inlet gas is utilized to produce the low temperature required for water condensation, thereby eliminating the need for an external power source.
A further object of the invention is to provide gas drying apparatus of a simple and reliable construction to function economically to remove water and oil from process gas with minimal maintenance and repair.
Other and further objects of the invention, together with the features of novelty appurtenant thereto, will appear in the course of the following description.